Sihota Ramanjit, Gulati Vikas, Agarwal Harish C, Saxena Rohit, Sharma Ajay, Pandey Ravindra M
Dr. R. P. Centre for Ophthalmic Sciences and Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, India.
J Glaucoma. 2002 Aug;11(4):321-8. doi: 10.1097/00061198-200208000-00008.
To study the test-retest variability of stereometric parameters on the Heidelberg Retina Tomograph II, a new clinical instrument for glaucoma management.
In a cross-sectional study of 24 consecutive cases of glaucoma and 26 healthy subjects, Heidelberg Retina Tomograph II stereometric parameters from five consecutive images were obtained for one randomly selected eye of each subject. Test-retest variability was studied using three different statistical methods (coefficient of variance, intraclass correlation coefficient, and Cronbach alpha). The effect of age, diagnosis, linear cup/disc ratio, visual acuity, and refractive error on test-retest variability on HRT II was analyzed. The repeatability of Moorfields regression analysis and the baseline variability in the progression analysis software was also studied.
Using coefficient of variance, intraclass correlation coefficient, and Cronbach alpha, the test-retest variability was found to be lowest for mean cup depth, cup area, cup/disc area ratio, vertical cup/disc ratio and rim/disc area ratio, in that order. Test-retest variability had a significant correlation with age (r = 0.33, P = 0.019) and visual acuity (r = -0.46, P = 0.005). Compared with eyes with astigmatism less than 1 D (mean coefficient of variance = 6.4 +/- 4.9), the test-retest variability was higher (P = 0.044) in eyes with astigmatism more than 1D (mean coefficient of variance = 20.0 +/- 22.6). Moorfields regression analysis was inconsistent in 52% cases. The average baseline change in progression analysis software was 0.076 +/- 0.081.
The test-retest variability of Heidelberg Retina Tomograph II stereometric parameters is comparable to that reported for the Heidelberg Retina Tomograph. Eyes with uncorrected astigmatism more than 1 D and poor visual acuity may have a higher variability of Heidelberg Retina Tomograph II stereometric parameters.
研究用于青光眼治疗的新型临床仪器海德堡视网膜断层扫描仪II（Heidelberg Retina Tomograph II，HRT II）立体测量参数的重测变异性。
在一项横断面研究中，对24例连续的青光眼患者和26名健康受试者进行研究，为每个受试者一只随机选择的眼睛获取连续五张图像的HRT II立体测量参数。使用三种不同的统计方法（方差系数、组内相关系数和Cronbach α系数）研究重测变异性。分析年龄、诊断、线性杯盘比、视力和屈光不正对HRT II重测变异性的影响。还研究了Moorfields回归分析的可重复性以及进展分析软件中的基线变异性。
使用方差系数、组内相关系数和Cronbach α系数，发现平均杯深、杯面积、杯/盘面积比、垂直杯/盘比和边缘/盘面积比的重测变异性依次最低。重测变异性与年龄（r = 0.33，P = 0.019）和视力（r = -0.46，P = 0.005）显著相关。与散光小于1 D的眼睛（平均方差系数 = 6.4 +/- 4.9）相比，散光大于1 D的眼睛（平均方差系数 = 20.0 +/- 22.6）重测变异性更高（P = 0.044）。Moorfields回归分析在52%的病例中不一致。进展分析软件中的平均基线变化为0.076 +/- 0.081。
海德堡视网膜断层扫描仪II立体测量参数的重测变异性与海德堡视网膜断层扫描仪报告的变异性相当。散光大于1 D且视力不佳的眼睛可能具有更高的海德堡视网膜断层扫描仪II立体测量参数变异性。
